Subjuntive

There are some expressions with you will always use the subjunctive... "antes de que" is one of them.

"que" is important because if the phrase is "antes de" without "que" we will use infinitive, not subjuntive.

Examples:

• Antes de que comiese fuimos a pescar. (always past)
• Before lunch we went fishing.

• Antes de comer fuimos a pescar. (past, chronological order)
• Before lunch we went fishing.

• Antes de comer iremos a pescar. (future, chronological order)
• Before lunch we will go fishing.

So the important thing and the diference is "que"

The most common uses of the subjunctive are:
1. express desire
2. express doubt
3. with expressions that always used subjunctive
4. in a negative order

1. Express desire
verbs: querer, esperar, necesitar,
expression: ojalá..
examples:
Espero que vengas a mi fiesta. (I hope you come to my party.)
Quiero que vengas a mi fiesta. (I want you to come to my party.)
Necesito que respondas la pregunta. (I need that you answer the question.)
Ojalá alcances tus sueños. (I hope you reach your dreams.)



2. Express doubt
expressions: quizás, posiblemente, tal vez,....
Quizás vaya mañana.
Posiblemente vaya mañana.
Tal vez vaya mañana.
(is the same thing-> Maybe, perhaps, I will come tomorrow)

3. expressions that always used subjunctive (but maybe not always but in most cases)
Es probable que
Es posible que
Es necesario que
Es conveniente que
Es mejor que
En caso que
A fin de que
Antes que, antes de que
Espero que
Deseo que
Dudo que
Dios quiera que

4. in a negative order
No fumes (don't smoke)
No bebas (don't drink)
No vayas (don't go)